The following relates generally to wireless communication, and more specifically to low latency physical uplink control channel (PUCCH) with scheduling requests (SR) and channel state information (CSI).
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example telecommunication standard is Long Term Evolution (LTE). LTE is designed to improve spectral efficiency, lower costs, improve services, make use of new spectrum, and better integrate with other open standards. LTE may use OFDMA on the downlink (DL), single-carrier frequency division multiple access (SC-FDMA) on the uplink (UL), and multiple-input multiple-output (MIMO) antenna technology. A wireless multiple-access communications system (including an LTE system) may include a number of base stations, each supporting communication for multiple communication devices, which may otherwise be known as user equipment (UE).
In some cases, a base station may transmit reference signals to a UE to aid in evaluating channel conditions. The UE may then send channel state information (CSI) reports to the base station periodically or when initiated by the base station. Periodic and base station-initiated CSI reports may be sufficient to determine current channel conditions. If the system supports low latency communications, however, the periodic and base station-initiated reports may be insufficient. This may result in dropped packets and delayed communications.